Timer



Sept. 9,1924.

1,507,744 F. LEDERER TIMER Filed ADIil 24 1922 INVINTOR.

ATTORNEYS.

Patented Sept. 9, 1924.

PATENT OFFICE.

FRIEDRICH LEDERER, E MILWAUKEE, WISC ONSIN.

TIMER.

To all whom it may concern:

Be it known that I, FRIEDRICH LEDERER,

a citizen of the United States, and resident of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Timers, of which the following is a description, reference being had to the accompanying drawings, which are a part of this specification. This invention relates to improvements in timers for automobile engines, and has for its object to provide a circuit making and breaking device of this character which will be simple in construction, comparatively in- 1 expensive to manufacture and install, and

more eflicient in use than those which have been heretofore proposed.

A further object of the invention is to provide a timer in which the stationary members comprise stamped sheet metal housings or casings, which may be rapidly and inexpensively manufactured, within which housings or casings are mounted yieldable contact plates.

A still further object of the invention is to so construct the said housings or casings as to efiiciently retain the said yieldable contact members in position therein, while .at the same time permitting. of their ready removal in case it is necessary or desired to renew the same.

A still further object of the invention is to provide a moving contact member of. symmetrical design in which the strains are equalized, thereby reducing the wear and tear upon the parts.

With these and other objects in view,

which will appear as thedescription proceeds, the invention consists in the novel details of construction and combinations of parts more fully hereinafter disclosed and particularly pointedout in theclaims.

In the accompanying drawings in which. like numerals designate like parts in all the views;

Figure 1 is a front elevational View, partly'in section, of a timer made in accordance with the present invention.

Fig. 2is a central sectional view taken approximately on the line 22 of Fig. 1 looking in the direction of the arrows.

Fig. 3 is a detail plan view of one of the contact members, as seen from the plane indicated by the line 33 of Fig. 1; and,

Application filed April 24, 1922. Serial No. 556,209.

Fig. 4 is a fragmentary detail sectional casing 2, or other fixed part of an internal combustion engine. Mounted within the said casing 1, about its inner circumference, are a plurality of contact members 3, which are symmetrically arranged around the said circumference at angles depending upon the number of cylinders which are to be controlled by the said timer, all as is well known.

The said contact members 3, comprise stamped sheet metal casings 4, having the side walls 5, the end walls 6, and the bottom 7, as will be clear from Figs. 1 and 3 of the drawings. The side of the housings opposite the wall 5 is left open and is adapted to be closed by the removable plate member 8, having the bent ears 9 engaging the end walls 6, as will be clear from Fig. 3. The said plates 8. are: secured in position by means of a screw or other fastening means 10, threaded into the rear end wall 5, of each of the said casing members.

The inner portions or ends of the end walls 6, are bent over to form the retaining lugs 11, which are adapted to hold the yieldable contact plates or blocks 12, in position, all as will appear more fully below.

The casing structure, just described, provides a substantially rectangular, hollow, box-like member. the bottom wall 7 of which is curved to fit the inner periphery of the timer housing 1. In order to secure the said contact casings to the timer housing, the said bottom walls are suitably perforated to receive the screws or other threaded members 13, which project therethrough and through the wall of the timer housing 1, as will be clear from Figs. 1 and 2.

A. strip of insulating material 14, is placed around the inner circumference of the timer housing 1, in order that the contact casings 3, may be insulated therefrom, and the holes or perforations in the said housing 1, through which the screws 13 pass, are bushed with the insulating washers or bushings 15. Other insulating washers 16 are interposed between the said timer housin l and the lock nuts 17, which are threaded upon said screws: '13,, and between which are clamped the leadwires 18, connecting the said timer with the spark plugs of the cylinders in the usual manner.

In order to yielda-bly maintain the contact blocks or plates 12, in their normal positions, a pair of springs 19, is mounted in each Off the said contact casings 3, at or near'the oppos te ends of the said contact blocks 12.

casing 1 inthe usual manner and. carries a moving contact member, comprising a sleeve -01". bushing 26, provided" with the angularly disposed flange 27, as will be clear from ,Figs... 1 and 2. A removable, disk or plate 28, is mounted upon the said sleeve 26 and there is secured between the flange 27 and the disk 28 at diametrically opposite points, a pair of cylindrical contact members 29. These said contact members are substantially rigidly' clamped between the said flange and disk by means of the screws 30, and are adapted to. make a sliding contact with the contact blocks-'12, as'will presently appear.

A suitable arm or lever 32. is provided for adjusting the parts relative to one another,

in order to control the time of the occurrence Of the spark, in the well knownmanner.

H The operation of the improved timer will 'beclea'r from the. foregoing but it can be briefly summarized as follows;

Upon rotation of the timer shaft 25, the moVmgcontact members .29 will be rotated in the usual manner and will be successively brought into contact with theyieldable contactblocks or members 12, carried by the j timer housing 1. As the said contact. membersare thus brought into engagement, the circuit to the spark plugs will be completed,

.thus causing the spark to occur within the ;-engine cylinders in the well known manner.

It will be noted that the contact members 29, although cylindrical in form, are; so

-mounted= astoprevent their rotation, so that a sliding, and not a rolling, contact is ob -.ta-ined. This sliding contact results ina much better transmission of the current, inasmuehas the contactsurfacesare maintained in a bright and; clean condition at alltimes.

flUhenever the members 29 become worn upon the surface which is engaging the contact members 12, the screws 30 may be loosened 7 and the members 29 rotated a small distance,

thereby bringing a new contact surface in position to engage the members 12;.

It will also be noted that a pair of contact members 29 is provided with members which are mounted at diametrically This construction results in a bala nced moving contact, whereby a great portion of the strains, incidental to the revolution of the timer shaft is eliminated.

It of course results from this construction that the circuit is completed through two of the spark plugs, at the same time; however, this is in no way disadvantageous,since when one cylinderis firing, the. cylinder which is connected to thecontact member 12 directly opposite thereto, is eXhaust-ing,.and the occurrence of the spark therein has no effect at all. V In fact the occurrence of the spark at this time tends to maintain the pointsof the spark plug in better condition, as it helps to maintain them free of carbon.

In Fig. .45 there is illustrated a slightly modified form of the movable contact member, wherein the cylindrical members29 are replaced by a member 3 5, which is substantially square in cross section. When this form of the invention is used, one, of the corners of thesaid member is positioned to engage with the contact members'12', and when. this said corner becomes worn the said member 35 may be turned inthe. same manner as members 29 to present anew corner for engagement. v

It isobvious that those skilled in the art may vary the details of constructiom as well 7 as the arrangement of parts, without departing from the spirit of .the invention, and therefore itis not wished to be limited to the above disclosure except as may be required by the claims.

What is claimed is; i

1. A device of the. class described comprising a housing; a hollow substantially ceiving casing secured to said housing, said casing being provided with retaining lugs, and with a readily removable side a contact block slidably mountedwithin said casing; and resilient means normally urgreadily removable side wall; a contact, mem-' ber slidably mountedwithin said casing; and

resilient means comprising springs-normally urging said contact member toward said lugs.

3. A device of the class descr becF comrectangular stamped sheet metal contact-reprising a housing; a hollow contact-receiv- I ing casing securedto said housing, said-casingbe ngprovided with end walls havlng integral inturned retaining lugs, and W1th a readily removable side wall; a contact block slidably mounted within said casing; aiplurality of springs behind said block normally urging said contact member toward said lugs; and means within. said casing for spacing said springs.

4. A device of the class described comprising a housing; a hollow contact-receiving casing secured to said housing, said casing being provided with end walls having integral inturned retaining lugs, and with a readily removable side wall; a contact block slidably mounted within said casing; a plurality of springs behind said block normally urging said contact member toward said lugs; and means within said casing for spac ing said springs, said means comprising U- shaped clips secured adjacent the bottom of said casing and forming with the walls thereof spring seats.

In testimony whereof, I aflix my si nature.

FRIEDRICH LEDE ER. 

